For me I'd buy the GTR just because I prefer it over the 370.
But for you, you have the knowledge and accessories etc to do pretty much anything to a car. I feel like you'd be bored with it just sat on your drive. (Although you'd still get all us turning up )
If I was in your shoes - I'd have more fun buying a car and making it different. Granted if you came to a Zed meet etc, you'd get all the attention in the GTR - but if you went to a GTR meet, what would you talk about/compare
Get a Supra/RX-7